A program of neuropsychological studies on clinical and theoretical problems in aphasia and brain laterality is proposed. Normative studies for the development of a more sensitive language evaluation and multivariate analysis of its predictive value will be carried out. The relation of sex to the incidence of aphasia will be studied in consecutive cases of acute stroke. Psycholinguistic studies at the level of phonology will deal with acoustic aspects of speech production and perception as well as variables at the suprasegmental level. At the lexical level, analysis of word finding difficulties will be carried out. An analysis of apraxia is planned to determine whether representational intent of a movement has any bearing on its adequacy of performance. Studies of cerebral dominance focus on testing the holistic-analytic hemisphere strategy theory on the study of right hemisphere contributions to reading, and on a new test of reliability of dichotic listening.